Service redirection from a policy and charging control architecture

ABSTRACT

For authorizing redirection services in a policy and charging control architecture, a policy and charging control rules function (PCRF) server determines control rules and redirection information per service in an internet protocol connectivity access network session, and a policy charging and enforcement function (PCEF) device receives control rules and redirection information per service basis, determines redirection per service request, and triggers the redirection. Upon a first request for a service, the PCEF device returns a redirection message with a redirection identifier; and upon completion of the service redirection, the first request for the service reaching the PCEF, the PCEF verifies the service is authorized and submits a service allowance toward the service server in charge of the service. Methods are also disclosed.

TECHNICAL FIELD

The present invention generally relates to authorization of services ina Policy and Charging Control architecture. More particularly, theinvention pertains to authorization of services that require aredirection.

BACKGROUND

The Policy and Charging Control (hereinafter PCC) functionality isdeployed in 3GPP TS 23.203 for Evolved 3GPP Packet Switched domain,including both 3GPP accesses (GERAN/UTRAN/E-UTRAN) and Non-3GPPaccesses.

The PCC architecture includes, amongst other entities, a Policy andCharging Control Rules Function (hereinafter PCRF) in charge of policycontrol decision and flow based charging control functionalities, aswell as in charge of provision of PCC rules to be enforced at the bearerlayer; a Policy and Charging Enforcement Function (hereinafter PCEF) incharge of service data flow detection based on filters included in thePCC rules received from the PCRF, as well as in charge of PCC rulesenforcement at the bearer layer; and an Application Function(hereinafter AF) for offering applications (in which the service isrequested at a signalling layer whereas it is delivered at a bearerlayer), the control of IP bearer resources according to what has beennegotiated. This AF transfers dynamic session information to the PCRF,namely description of the media to be delivered at the bearer layer.

Regarding the communication between the above PCC entities, as disclosedin 3GPP TS 23.203, PCRF and PCEF communicate through a so-called Gxinterface, whereas PCRF and AF communicate through a so-called Rxinterface. In particular, the PCRF thus provides control rules to thePCEF through this Gx interface, whereas the AF provides the descriptionof the media to be delivered at the bearer layer to the PCRF throughthis Rx interface.

Regarding the control rules submitted from the PCRF to the PCEF, thesecontrol rules include, although are not limited to, those PCC rulesdisclosed in 3GPP TS 23.203, and can be provided upon establishment ormodification of an IP Connectivity Access Network (hereinafter IP-CAN)session.

Moreover, these control rules are determined or generated by the PCRFbased on: information obtained from the AF via the Rx reference point,for example, the description of the media commented above, session data,and subscriber related information; information obtained from the PCEFthrough the Gx interface, for example IP-CAN bearer attributes, requesttype, subscriber related information and location information;information obtained from a Subscription Profile Repository (hereinafterSPR) through a so-called Sp interface, for example, subscriber andservice related data; and other locally configured information at thePCRF.

Regarding the description of the media to be delivered at the bearerlayer, which is provided from the AF to the PCRF, the description of themedia may include one or more media components. A media component can beregarded as a portion of an AF session conveying information aboutmedia, such as media type, format, IP address, port(s), transportprotocol, bandwidth, and direction. In this respect, the media describedby a media component can be either bi- or unidirectional. On the otherhand, media using the so-called Real-time Transport Protocol(hereinafter RTP) for transport may also have associated RTCP. If so,the media component also conveys information about the associated RTPControl Protocol (hereinafter RTCP), such as port and possiblybandwidth. Moreover, each media component may include mediasubcomponents, wherein each media subcomponent can be regarded as aportion of a media component describing a bi- or unidirectional IP flow.

At present, a huge variety of Internet Services have been developedwherein a user accessing a particular service site is redirected towardsa different service site or Web portal. In particular, someuser-initiated traffic may be redirected to an information page, whereusers can be informed about their current usage, or about a tariffchange due to roaming, or because the user is out of his time range.Moreover, users might be requested to perform actions such asconfirmation or acceptance of new conditions, buy a voucher, etc.

However, current PCC procedures and architectural elements are notprepared to handle this sort of redirection services and there is thus aneed to determine in the PCC architecture what services require aredirection, and can be considered to be redirection services, whatpolicies to apply and how to properly charge such redirection services;and, more specifically, in those scenarios where an effective serviceauthorization depends on actions carried out during the redirection.

SUMMARY

The present invention is aimed to overcome or, at least, to mitigate theabove drawbacks and provides for a new PCRF server and a new PCEF devicearranged for supporting service redirections, and a new method ofauthorizing a service redirection in a PCC architecture.

In accordance with a first aspect of the present invention, there isprovided a method of authorizing a service with a PCC architecture.

This method comprises the steps of: upon establishment or modificationof an IP-CAN session with a UE, a PCEF device requesting control rulesto a PCRF server; determining at the PCRF server control rules to beapplied per service basis for the IP-CAN session; determining at thePCRF server, based on redirection policy criteria, those services forwhich a redirection is required; submitting from the PCRF server to thePCEF device the control rules and redirection information per servicebasis; installing at the PCEF device the received control rules andredirection information per service basis, an enforcing said controlrules per services basis; upon a first service request from the UE for aservice identified by a service destination identifier, the PCEF devicedetermining that the service requires redirection and returning towardsthe UE a redirection message with a service redirection identifier andthe service destination identifier; upon completion of serviceredirection, the first service request for the service identified by theservice destination identifier reaching again the PCEF device; verifyingat the PCEF device that the service identified by the servicedestination identifier can be authorized; and submitting a serviceallowance message for the first service request from the PCEF devicetowards a service server handling the service identified by the servicedestination identifier.

In particular, the redirection information per service basis may includea redirection activation indicator indicating whether the redirection isto be set or not for the service, and the service redirection identifierindicating where the UE is to be redirected for the service. Moreover,where the service destination identifier is a destination URI addressingthe service server, the service redirection identifier may be aredirection URI addressing a site where the UE is to be redirected.

In order to provide a more autonomous handling of redirections to thePCEF device, the redirection information per service basis may furtherinclude a redirection expiry selected from: a time value during whichredirection takes place, an event for which the redirection is set orreset, and a one-time indicator indicating the redirection for the firstservice request in the IP-CAN session and no further redirection forsubsequent service requests in the IP-CAN session.

Particularly useful in this method, where the redirection informationper service basis includes the one-time indicator, the method mayfurther include a step of disarming the redirection after havingredirected the first service request from the UE for the service, thatis, the first request for a particular service.

Then, upon a second service request from the UE for the service, thatis, a second or successive request for the same particular service, themethod may further include a step of authorizing the service at the PCEFdevice without redirection, and a step of submitting a service allowancefor the second service request from the PCEF device towards the serviceserver handling the service identified by the service destinationidentifier.

Apart from that, the redirection information per service basis mayfurther include at least one of: a redirection code indicating a reasonfor redirection, and a redirection confirmation indicating whether thePCRF server requires confirmation when redirection has been applied.

On the other hand, the redirection policy criteria may include at leastone of dynamic conditions and usage conditions. In particular, thedynamic conditions may indicate whether the UE is in a roaming conditionor in a non-roaming condition, or radio access type, or location, orcombinations thereof, etc. Also in particular, the usage conditions mayindicate the accumulated usage for the IP-CAN session, the usage limitfor the IP-CAN session, the reset period for the accumulated usage,combinations thereof, etc.

In accordance with a second aspect of the present invention, there isprovided a new PCEF device for enforcing control rules applicable duringan IP-CAN session established with a UE.

This PCEF device comprises: a processing unit arranged for determiningestablishment or modification of an IP-CAN session with UE; a firstinterfacing unit arranged for requesting control rules to a PCRF serverin charge of generating the control rules, and arranged for receivingthe control rules and redirection information per service basis from thePCRF server; and wherein the processing unit is arranged for installingthe received control rules and the redirection information per servicebasis.

This PCEF device also comprises a second interfacing unit arranged forreceiving a service request from the UE for a service identified by aservice destination identifier; wherein the processing unit is arrangedfor determining that the service requires redirection and is arrangedfor determining a service redirection identifier; and wherein the secondinterfacing unit is arranged for returning towards the UE a redirectionmessage with the service redirection identifier and with the servicedestination identifier, and is arranged for receiving again, uponcompletion of the service redirection, the service request for theservice identified by the service destination identifier.

The processing unit of this PCEF device is also arranged for verifyingthat the service identified by the service destination identifier can beauthorized; and the PCEF device further comprises a third interfacingunit arranged for submitting a service allowance message for the servicerequest towards a service server handling the service identified by theservice destination identifier.

In particular, this PCEF device may further comprise a storing unitarranged for storing the redirection information per service basis,wherein the redirection information may include: a redirectionactivation indicator indicating whether the redirection is to be set ornot for the service, and the service redirection identifier indicatingwhere the UE is to be redirected for the service. Moreover, the storingunit may be arranged for storing the service destination identifier as adestination URI addressing the service server and for storing theservice redirection identifier as a redirection URI addressing a sitewhere the UE is to be redirected.

As already commented above, and in order to provide a more autonomoushandling of redirections to the PCEF device, the storing unit of thisPCEF device may be arranged for storing the redirection information perservice basis, the redirection information including a redirectionexpiry selected from: a time value during which redirection takes place,an event for which the redirection is set or reset, and a one-timeindicator indicating the redirection for the first service request inthe IP-CAN session and no further redirection for subsequent servicerequests in the IP-CAN session.

Particularly useful in this case, where the redirection information perservice basis includes the one-time indicator, the processing unit ofthe PCEF device may further be arranged for disarming the redirectionafter having redirected the service request from the UE for the service.

Then, upon a subsequent service request for the service received at thesecond interfacing unit from the UE, the processing unit of the PCEFdevice may be arranged for authorizing the service without redirectionand the third interfacing unit may be arranged for submitting a serviceallowance message for the subsequent service request towards the serviceserver handling the service identified by the service destinationidentifier.

In accordance with a third aspect of the present invention, there isprovided a new PCRF server for generating control rules to be enforcedby a PCEF device during an IP-CAN session established with a UE.

This PCRF server comprises: an interfacing unit arranged for receiving arequest for control rules from a PCEF device in charge of enforcing thecontrol rules; a processing unit arranged for determining control rulesto be applied per service basis for the IP-CAN session; and arranged fordetermining, based on redirection policy criteria, those services forwhich a redirection is required; and wherein the interfacing unitarranged for submitting to the PCEF device the control rules andredirection information per service basis. The PCRF server may furthercomprise a storing unit arranged for storing the redirection informationper service basis. In particular, this redirection information perservice basis may include: a redirection activation indicator indicatingwhether the redirection is to be set or not for the service, and aservice redirection identifier indicating where the UE is to beredirected for the service. In particular, the storing unit of the PCRFserver may be arranged for storing the service redirection identifier asa redirection URI addressing a site where the UE is to be redirected.

Aligned with corresponding features commented above, and in order toprovide a more autonomous handling of redirections to the PCEF device,the storing unit of the PCRF server may be arranged for storing theredirection information per service basis, this redirection informationmay include a redirection expiry selected from: a time value duringwhich redirection takes place, an event for which the redirection is setor reset, and a one-time indicator indicating the redirection for thefirst service request in the IP-CAN session and no further redirectionfor subsequent service requests in the IP-CAN session.

Apart from that, the redirection policy criteria to be used by the PCRFserver in determining service redirection per service basis may includeat least one of dynamic conditions and usage conditions. Therefore, thestoring unit of the PCRF server may be arranged for storing theredirection policy criteria. In particular, the dynamic conditions mayindicate whether the UE is in a roaming condition or in a non-roamingcondition, or radio access type, or location, or combinations thereof,etc; and the storing unit of the PCRF server may be arranged for storingthese dynamic conditions. Also in particular, the usage conditions mayindicate the accumulated usage made for the IP-CAN session, the usagelimit set for the IP-CAN session, the reset period for the accumulatedusage, combinations thereof, etc; and the storing unit of the PCRFserver may be arranged for storing these usage conditions.

On the other hand, the invention may be practised by a computer program,in accordance with a fourth aspect of the invention, the computerprogram being loadable into an internal memory of a computer with inputand output units as well as with a processing unit, and comprisingexecutable code adapted to carry out the above method steps. Inparticular, this executable code may be recorded in a carrier readablein the computer.

BRIEF DESCRIPTION OF THE DRAWINGS

The features, objects and advantages of the invention will becomeapparent by reading this description in conjunction with theaccompanying drawings, in which:

FIG. 1 illustrates a simplified view of the sequence of actions to beperformed in order to determine those services that require aredirection, and to provide appropriate control rules and redirectioninformation towards the bearer layer.

FIG. 2 shows a simplified view of the sequence of actions to beperformed in accordance with the invention to redirect a first requestreceived for an exemplary first service.

FIG. 3 shows a simplified view of the sequence of actions to beperformed in accordance with the invention to redirect a first requestreceived for an exemplary second service.

FIG. 4 shows exemplary sequence of actions to be performed for disarmingredirection condition for different services.

FIG. 5 illustrates a simplified view of PCC architecture.

FIG. 6 illustrates a basic implementation of a PCEF device provided forin accordance with embodiments of the invention.

FIG. 7 illustrates a basic implementation of a PCRF server provided forin accordance with embodiments of the invention.

DETAILED DESCRIPTION

The following describes currently preferred embodiments of a PCRF serverand a PCEF device, both operating in accordance with PCC architecture,and a method of authorizing a service for which a redirection may bedetermined by the PCC architecture.

FIG. 5 basically illustrates structural elements of the PCC architectureas disclosed in 3GPP TS 23.203 v10.1.0. In this PCC architecture, apartfrom the PCRF 1 a, PCEF 2 a and AF 7 already discussed above, FIG. 5shows a Bearer Binding and Event Reporting Function (hereinafter BBERF)2 b, which may be considered as a PCEF located in a visited network,interfacing with the PCRF 1 a through a so-called S7x interface; aSubscription Profile Repository (hereinafter SPR) 6, which storessubscription data for users, interfacing with the PCRF 1 a through aso-called Sp interface; an Online Charging System (hereinafter OCS) 8,which is in charge of handling online credit control for service dataflow based charging, interfacing with the PCEF 2 a through a so-calledGy interface; and an Offline Charging System (hereinafter OFCS) 9, whichis in charge of handling offline credit control for service data flowbased charging, interfacing with the PCEF 2 a through a so-called Gzinterface.

A conventional PCC architecture as shown in FIG. 5 may include the PCRFserver 1 and the PCEF device 2, as disclosed throughout the presentspecification, in order to carry out the functions of conventional PCRF1 a and PCEF 2 a, as well as the distinguishing features provided for inaccordance with the present invention and further discussed in thefollowing. In particular, for the purpose of the present invention, thedistinguishing features disclosed throughout the present specificationin respect of the PCEF device 2 may well be applicable to, and includedin, any BBERF server carrying out the functions of conventional BBERF 2b.

The FIG. 1 illustrates a sequence of actions that may be performed indetermining those services that require a redirection. As FIG. 1illustrates, establishment of an IP-CAN session with user equipment(hereinafter UE) 3 is carried out at the PCEF device 2 during a stepS-100. In particular, the IP-CAN session establishment may be indicatedby receiving at the PCEF device a so-called ‘PDP Context Activation’from a UE, where the UE has accessed through a GPRS access network. Insuch particular case, the PCEF device may be included in a Gateway GPRSSupport Node (hereinafter GGSN). More generally speaking, where theaccess network is other than a GPRS network, such as a wireless localarea network (hereinafter WLAN), a 3^(rd) generation (hereinafter 3G) or4^(th) generation (hereinafter 4G) access networks may be, the PCEFdevice 2 may be included in a corresponding gateway 2 c, which isillustrated in FIG. 5, located at the bearer layer.

Moreover, even if not illustrated in any drawing, a similar behaviour asfor the establishment of an IP-CAN session can be expected for thepurpose of the present invention upon receipt at the PCEF device 2 of anIP-CAN session modification from the UE 3. Consequently, the followingsequence of actions illustrated in FIG. 1, and carried out uponestablishment of the IP-CAN session modification, can well be applied aswell upon modification of an IP-CAN session previously established atthe PCEF device 2 with the UE 3.

Still with reference to FIG. 1, upon establishment of the IP-CAN sessionwith the UE 3 or upon modification of a previously established IP-CANsession, the PCEF device 2 requests during a step S-105 control rules tothe PCRF server 1 for the IP-CAN session. In particular, this requestmay be carried out by submitting a so-called CCR message through the Gxinterface.

The PCRF server 1 determines during a step S-110 control rules to beapplied per service basis. In this respect, more than one differentservice may be invoked during a same IP-CAN session. In addition, duringa step S-115 the PCRF server 1 may also determine per service basis, andbased on redirection policy criteria, whether or not redirection isrequired. To this end, the PCRF server 1 might request previously or inparallel to the actions carried out during the steps S-110 or S-115service data from the SPR 6 commented above, through the Sp interfaceillustrated in FIG. 5.

In particular, the redirection policy criteria may include at least oneof dynamic conditions and usage conditions. In particular, the dynamicconditions may indicate whether the UE is in a roaming condition or in anon-roaming condition, or radio access type, or location, orcombinations thereof, etc. Also in particular, the usage conditions mayindicate the accumulated usage for the IP-CAN session, the usage limitfor the IP-CAN session, the reset period for the accumulated usage,combinations thereof, etc.

Then, back to the actions illustrated in FIG. 1, the PCRF server 1submits to the PCEF device 2 during a step S-120 the control rules andredirection information determined per service basis. In particular,this submission may be carried out by submitting a so-called CCA messagethrough the Gx interface to the PCEF device. The PCEF device 2 installsthe received control rules and redirection information per service basisduring a step S-125 and enforces said control rules for traffic flows inthe IP-CAN session.

In particular, the redirection information per service basis may includea redirection activation indicator indicating whether the redirection isto be set or not for the service, and a service redirection identifierindicating where the UE is to be redirected when requesting the service.

Some sequences of actions that may occur from this stage onwards, andwhich may be relevant for the purpose of the present invention, areexemplary depicted in FIG. 2 and FIG. 3 and discussed in the following.

For instance, FIG. 2 illustrates a sequence of actions to be carried outfor an exemplary first service, whereas FIG. 3 illustrates another foran exemplary second service.

The sequence of actions illustrated in FIG. 2 starts with the receptionat the PCEF device 2 during a step S-130 of a first request for theexemplary first service. In this respect, this exemplary first serviceis identified by a service destination identifier included in the firstrequest. In particular, this service destination identifier may be adestination URI addressing the service server 5 in charge of executingor running the exemplary first service.

Then, the PCEF device 2 may determine during a step S-135 that thisexemplary first service requires redirection. In such a case, the PCEFdevice 2 may return during a step S-140 towards the UE 3 a redirectionmessage with a service redirection identifier and the received servicedestination identifier. In particular, the service redirectionidentifier may be a redirection URI addressing a redirection site 4(hereinafter R-site) where the UE 3 is to be redirected.

The UE 3 receiving the redirection message from the PCEF device 2redirects during a step S-145 the first request for the exemplary firstservice towards the R-site 4. The UE 3 may be requested to perform anyaction there, such as confirmation or acceptance of new serviceconditions, buy a voucher, etc. Once any required action has beenperformed, the R-site 4 issues during a step S-150 a service responsefor the exemplary first service towards the UE 3.

Once the service response for the exemplary first service is received atthe UE 3, the redirection is completed and the original first requestfor the exemplary first service is submitted again towards the PCEFdevice 2 during a step S-155. The request also including the servicedestination identifier.

Optionally, and not illustrated in any drawing, the PCEF device 2 couldreceive a confirmation from the R-site 4 indicating that the redirectionhad been completed, and this confirmation might likely be submitted fromthe PCEF device 2 to the PCRF server 1. Alternatively, the confirmationmay optionally be submitted from the R-site 4 directly to the PCRFserver. These alternative options may be advantageous where a differentoperational handling is wanted for first and subsequent requests for anyparticular service.

The PCEF device 2, as receiving again the first request for theexemplary first service, verifies during a step S-160 that thisexemplary first service, which is identified by the service destinationidentifier, can be authorized and the PCEF device may submit during astep S-165 a service allowance message for this exemplary first servicetowards the service server 5 in charge of handling the exemplary firstservice. In particular, where the service destination identifier is adestination URI, the service server may be addressed by such destinationURI.

Moreover, in accordance with an embodiment of the invention, theredirection information per service basis may further include at leastone of: a redirection code indicating a reason for redirection, and aredirection confirmation indicating whether the PCRF server requiresconfirmation when redirection has been applied.

For example, the embodiment illustrated in FIG. 3 starts with thereception at the PCEF device 2 during a step S-170 of a first requestfor an exemplary second service. As for the above embodiment discussedwith reference to FIG. 2 for an exemplary first service, this exemplarysecond service is also identified by a service destination identifierincluded in this first request. In particular, this service destinationidentifier may be also a destination URI addressing the service server 5in charge of executing or running the exemplary first service.

The PCEF device 2 may then determine during a step S-175 that thisexemplary second service requires redirection, and the PCEF device 2 mayreturn during a step S-180 towards the UE 3 a redirection message with aservice redirection identifier and the received service destinationidentifier. In particular, the service redirection identifier may bealso a redirection URI addressing an R-site 4 where the UE 3 is to beredirected.

The UE 3 receiving the redirection message from the PCEF device 2redirects during a step S-185 the first request for the exemplary secondservice towards the R-site 4, wherein the UE 3 may be requested toperform any action. Once any required action has been performed, theR-site 4 issues during a step S-190 a service response for the exemplarysecond service towards the UE 3.

As for the above embodiment discussed with reference to FIG. 2 for anexemplary first service, optionally and not illustrated in any drawing,the PCEF device 2 might also receive under this embodiment aconfirmation from the R-site indicating that the redirection had beencompleted. Alternatively, the PCEF device 2 may wait during a time gapafter having submitted the redirection message towards the UE 3, or mayproceed in parallel to submit a confirmation to the PCRF server 1indicating redirection has been applied.

Whatever alternative is configured, taking into account those featuressupported by the PCEF device and the PCRF server, the PCEF device 2 maysubmit a confirmation to the PCRF server 1 during a step S-195indicating the redirection of the UE 3 to the R-site 4. To this end, theso-called CCR message may be used through the Gx interface from the PCEFdevice 2 towards the PCRF server 1 including the confirmation ofredirection.

On the other hand, as already commented above and not illustrated in anydrawing, the R-site 4 may directly submit a confirmation to the PCRFserver 1 indicating that the redirection had been completed. Where thisalternative is carried out, the confirmation discussed immediatelyabove, whereby the PCEF device 2 confirms during the step S-195 thecompletion of redirection to the PCRF server likely with a CCR message,may be superfluous and omitted in this sequence of actions illustratedin FIG. 3.

As a result of confirming the completion of redirection to the PCRFserver 1 by any alternative discussed above, the PCRF server 1 maydetermine some additional or alternative redirection information, andreturn this additional or alternative redirection information to thePCEF device 2 during a step S-200. To this end, the so-called CCAmessage may be used through the Gx interface from the PCRF server 1towards the PCEF device 2 including the additional or alternativeredirection information, if any.

If such additional or alternative redirection information were included,it would be installed for the exemplary second service at the PCEFdevice 2, and would be applied for this first request for the exemplarysecond service, if still on time, or for further requests for theexemplary second service, if the first request has already been treatedor is not involved in such additional or alternative redirectioninformation.

Once the service response for the exemplary first service had beenreceived at the UE 3, the redirection is completed. Then, the UE 3submits the original first request for the exemplary second servicetowards the PCEF device 2, and the latter receives again during a stepS-205 such first request for the exemplary second service. The requestalso including the service destination identifier.

The PCEF device 2, as receiving again the first request for theexemplary second service, verifies during a step S-210 that thisexemplary second service, which is identified by the service destinationidentifier, can be authorized and the PCEF device may submit during astep S-215 a service allowance message for this exemplary second servicetowards the service server 5 in charge of handling the exemplary secondservice. In particular, where the service destination identifier is adestination URI, the service server may be addressed by such destinationURI.

In order to carry out embodiments of the above method, there is providedin accordance with an embodiment of the invention a PCRF server 1, asillustrated in FIG. 6, for generating control rules to be enforced bythe PCEF device 2 for an IP-CAN session established with a UE 3, and aPCEF device 2, as illustrated in FIG. 7, for enforcing the control rulesapplicable for the IP-CAN session established with the UE 3.

This PCRF server 1 illustrated in FIG. 6 comprises an interfacing unit30 arranged for receiving a request for control rules from a PCEF device2 in charge of enforcing the control rules; a processing unit 20arranged for determining control rules to be applied per service basisfor the IP-CAN session; and arranged for determining, based onredirection policy criteria, those services for which a redirection isrequired. The interfacing unit 30 of this PCRF server is arranged forsubmitting to the PCEF device the control rules and redirectioninformation per service basis. In particular, the interfacing unit 30may be arranged for receiving the request for control rules in aso-called CCR message through the Gx interface, and for submitting tothe PCEF device the control rules and redirection information in aso-called CCA message through the Gx interface. More particularly, theinterfacing unit 30 may include a sender 40 for submissions towards thePCEF device and a receiver 50 for receptions from the PCEF device.

Apart from that, the PCRF server 1 may further comprise a storing unit10 arranged for storing the redirection information per service basis.This redirection information per service basis may include a redirectionactivation indicator indicating whether the redirection is to be set ornot for the service, and a service redirection identifier indicatingwhere the UE is to be redirected for the service. In particular, thestoring unit 10 may be arranged for storing the service redirectionidentifier as a redirection URI addressing the R-site 4 where the UE isto be redirected.

As already commented above, the redirection policy criteria may includeat least one of dynamic conditions and usage conditions. Therefore, thestoring unit 10 of the PCRF server 1 may be arranged for storing theredirection policy criteria. In particular, the dynamic conditions mayindicate whether the UE is in a roaming condition or in a non-roamingcondition, or radio access type, or location, or combinations thereof,etc; and the storing unit 10 of the PCRF server 1 may be arranged forstoring these dynamic conditions. Also in particular, the usageconditions may indicate the accumulated usage made for the IP-CANsession, the usage limit set for the IP-CAN session, the reset periodfor the accumulated usage, combinations thereof, etc; and the storingunit 10 of the PCRF server 1 may be arranged for storing these usageconditions.

The PCEF device 2 illustrated in FIG. 7 comprises a processing unit 25arranged for determining establishment or modification of an IP-CANsession with a UE 3; a first interfacing unit 45 arranged for requestingcontrol rules to the PCRF server 1 in charge of generating the controlrules; and arranged for receiving the control rules and redirectioninformation per service basis from the PCRF server 1; and wherein theprocessing unit is arranged for installing the received control rulesand the redirection information per service basis as well as forenforcing said control rules per service basis. In particular, theinterfacing unit 45 may be arranged for requesting the control ruleswith a so-called CCR message through the Gx interface, and for receivingfrom the PCRF server the control rules and redirection information in aso-called CCA message through the Gx interface.

The PCEF device 2 also comprises a second interfacing unit 55 arrangedfor receiving a service request from the UE for a service identified bya service destination identifier; and wherein the processing unit isarranged for determining that the service requires redirection and fordetermining a service redirection identifier. In particular, this secondinterfacing unit 55 is arranged for receiving from the UE 3 anyestablishment or modification of an IP-CAN session.

Moreover, the second interfacing unit 55 of the PCEF device 2 is alsoarranged for returning towards the UE a redirection message with theservice redirection identifier and with the service destinationidentifier; and is also arranged for receiving again, upon completion ofthe service redirection, the service request for the service identifiedby the service destination identifier; whereas the processing unit 25 isarranged for verifying that the service identified by the servicedestination identifier can be authorized.

Furthermore, the PCEF device 2 also includes a third interfacing unit 65arranged for submitting a service allowance message for the servicerequest towards a service server 5 handling the service identified bythe service destination identifier.

In particular, the first, second and third interfacing units of the PCEFdevice 2 may be provided as respectively separate units 45, 55 and 65,or as an integral interfacing unit arranged for communicating with thePCRF server 1, the UE 3 and the service server 5.

In addition, the PCEF device 2 may further comprise a storing unit 15for storing the redirection information per service basis. Thisredirection information may include a redirection activation indicatorindicating whether the redirection is to be set or not for the service,and the service redirection identifier indicating where the UE is to beredirected for the service. In particular, the storing unit 15 may bearranged for storing the service destination identifier as a destinationURI addressing the service server 5 and for storing the serviceredirection identifier as a redirection URI addressing the R-site 4where the UE is to be redirected.

Apart from what has been commented above with regard to the redirectioninformation, and which may be applicable for both above embodiments,some more operational information elements can be included in theredirection information in order to better adapt the PCC architecture todifferent handling of services for different services, and being stillcompatible with the above embodiments.

In this respect, in accordance with an embodiment of the invention fullycompatible with the above previous embodiments, the redirectioninformation per service basis may further include a redirection expiryselected from: a time value during which redirection takes place, anevent for which the redirection is set or reset, and a one-timeindicator indicating the redirection for the first service request inthe IP-CAN session and no further redirection for subsequent servicerequests in the IP-CAN session.

These operational information elements, which are usable in determiningthe redirection expiry for any particular service, allow forinterrupting, or even stopping, the redirection for further requestsrelated to any particular service. For instance, where the redirectioninformation includes as redirection expiry a time value during whichredirection takes place, a timer is triggered at the PCEF device 2 wheninstalling the redirection information for the particular service and,upon expiry of such timer, the redirection is stopped for subsequentrequests for the particular service. As a further instance, where theredirection information includes as redirection expiry an event forwhich the redirection is set or reset, the PCEF device 2 tracks theperformance of the particular service to detect such event; for example,where an explicit acceptance by the UE of amended service conditions isto be required and after that acceptance no further redirection takesplace for subsequent requests for the particular service. As a stillfurther instance, where the redirection information includes asredirection expiry an one-time indicator indicating the redirection forthe first service request in the IP-CAN session and no furtherredirection for subsequent service requests in the IP-CAN session, thePCEF device 2 may, on its own and without further participation of thePCRF server 1, stop the redirection for subsequent requests for theparticular service, once the redirection for the first request has beenaccomplished; this may be particularly useful where the redirectiontakes place only to inform the UE of any particular service feature orwhere no explicit action by the UE is required other than visiting theR-site.

FIG. 4 illustrates some embodiments for different services for whichsome of the above redirection expiry elements had been determined at thePCRF server 1 and installed at the PCEF device 2.

As shown in FIG. 4, the PCEF device may disarm during a step S-220 theredirection for the exemplary second service. This may be due to theadditional or alternative redirection information lately received at thePCEF device 2 from the PCRF server 1 for the exemplary second serviceduring the step S-200 and already discussed above with reference to FIG.3. More particularly, additional or alternative redirection informationmay have included a particular event for which the redirection is reset,such as once the first request has been allowed.

Apart from that, even if no additional or alternative redirectioninformation had been received during the previous step S-200, thesequence of actions illustrated for the exemplary second service in FIG.4 may also be due to the receipt of an one-time indicator as redirectionexpiry at the PCEF device indicating the redirection for the firstrequest of the exemplary second service in the IP-CAN session and nofurther redirection for subsequent requests of the exemplary secondservice in the IP-CAN session.

That is, where the redirection information for a particular serviceincludes the one-time indicator, the method further includes a stepS-220 of disarming the redirection after having redirected the firstservice request from the UE for the particular service.

Even if FIG. 4 shows this step of disarming the redirection only for theexemplary second service, for which additional or alternativeredirection information might have been received as illustrated in FIG.3, the receipt of an one-time indicator as redirection expiry for thefirst exemplary service at the PCEF device, which is not illustrated inany drawing, also makes the PCEF device disarming the redirection afterhaving redirected the first service request from the UE for theexemplary first service, so that no further redirection for subsequentrequests of the exemplary first service in the IP-CAN session occur.

Thus, where the redirection has been disarmed at the PCEF device 2 forthe exemplary second service, a second request for the exemplary secondservice received at the PCEF device 2 during a step S-225, as shown inFIG. 4, is determined not to be redirected, and the PCEF device 2 canverify during a step S-230 that this exemplary second service, which isidentified by the service destination identifier, can be authorized.

Then, the PCEF device may submit during a step S-235 a service allowancemessage for this exemplary second service towards the service server 5in charge of handling the exemplary second service. In particular, wherethe service destination identifier is a destination URI, the serviceserver may be addressed by such destination URI.

On the other hand, FIG. 4 also shows an embodiment representative of acase where the redirection information for the exemplary first servicehad included as redirection expiry a time value during which redirectiontakes place. As already commended above, a timer was triggered at thePCEF device 2 when installing the redirection information for thisexemplary first service, which is not illustrated in any drawing.

As shown in FIG. 4, upon expiry of such timer during a step S-250 forthe exemplary first service, the PCEF device 2 may disarm during a stepS-255 the redirection for the exemplary first service.

Afterwards, a second request for the exemplary first service received atthe PCEF device 2 during a step S-260, as shown in FIG. 4, is determinednot to be redirected, and the PCEF device 2 can verify during a stepS-265 that this exemplary first service, which is identified by theservice destination identifier, can be authorized.

As for the previous embodiment shown for the exemplary second service inthis FIG. 4, the PCEF device may also submit during a step S-270 aservice allowance message for this exemplary first service towards theservice server 5 in charge of handling the exemplary first service. Inparticular, where the service destination identifier is a destinationURI, the service server may be addressed by such destination URI.

That is, after having disarmed the redirection for any particularservice, such as the exemplary first and second services, and due to anyof the reasons discussed above in respect of FIG. 4, upon a furtherrequest from the UE for the particular service, the method furtherincludes a step of authorizing the particular service at the PCEF devicewithout redirection, and a step of submitting a service allowance forthe further request from the PCEF device towards the service serverhandling the service identified by the service destination identifier.

In order to carry out advantageous embodiments of the above method, thestoring unit 10 of the PCRF server 1 illustrated in FIG. 6 may bearranged for storing the redirection information per service basis,wherein the redirection information further includes a redirectionexpiry selected from: a time value during which redirection takes place,an event for which the redirection is set or reset, and a one-timeindicator indicating the redirection for the first service request inthe IP-CAN session and no further redirection for subsequent servicerequests in the IP-CAN session.

Likewise, the storing unit 15 of the PCEF device 2 illustrated in FIG. 7may be arranged for storing the redirection information per servicebasis, wherein the redirection information further includes aredirection expiry selected from: a time value during which redirectiontakes place, an event for which the redirection is set or reset, and aone-time indicator indicating the redirection for the first servicerequest in the IP-CAN session and no further redirection for subsequentservice requests in the IP-CAN session. Moreover, where the redirectioninformation per service basis includes the one-time indicator, theprocessing unit 25 of the PCEF device 2 may be further arranged fordisarming the redirection after having redirected the service requestfrom the UE for the service. Furthermore, after having disarmed theredirection, upon a subsequent service request for the service receivedat the second interfacing unit 55 from the UE, the processing unit 25may be arranged for authorizing the service without redirection, and thethird interfacing unit 65 may be arranged for submitting a serviceallowance message for the subsequent service request towards the serviceserver 5 handling the service identified by the service destinationidentifier.

The invention may also be practised by a computer program, loadable intoan internal memory of a computer with input and output units as well aswith a processing unit. This computer program comprises to this endexecutable code adapted to carry out the above method steps when runningin the computer. In particular, the executable code may be recorded in acarrier readable means in a computer.

The invention is described above in connection with various embodimentsthat are intended to be illustrative and non-restrictive. It is expectedthat those of ordinary skill in this art may modify these embodiments.The scope of the invention is defined by the claims in conjunction withthe description and drawings, and all modifications that fall within thescope of the claims are intended to be included therein.

The invention claimed is:
 1. A method of authorizing a service with apolicy and charging control (PCC) architecture, the method comprising:upon establishment or modification of an internet protocol (IP)connectivity access network (IP-CAN) session with a user equipment (UE),requesting, by a policy and charging enforcement function (PCEF) device,PCC rules from a policy and charging control rules function (PCRF)server; responsive to receiving the request for PCC rules, at the PCRFserver, upon establishment or modification of the IP-CAN session:determining, at the PCRF server, PCC rules to be applied per servicebasis for the IP-CAN session; determining, at the PCRF server based onredirection policy criteria, a service for which a redirection isrequired; submitting, from the PCRF server to the PCEF device, the PCCrules per service basis and redirection information for the service forwhich the redirection is required, wherein the redirection informationfor the service for which the redirection is required includes a serviceredirection identifier indicating where the UE is to be redirected forthe service for which the redirection is required; installing, at thePCEF device, the received PCC rules per service basis and theredirection information for the service for which the redirection isrequired; upon a first service request from the UE for a serviceidentified by a service destination identifier, determining, by the PCEFdevice based on the redirection information received from the PCRF andthe PCC rules per service basis, that the service identified by theservice destination identifier is the service for which redirection isrequired, and returning toward the UE a redirection message with theservice redirection identifier and the service destination identifier;and after completion of service redirection the first service requestfor the service identified by the service destination identifierreaching again the PCEF device; verifying at the PCEF device that theservice identified by the service destination identifier can beauthorized; and submitting a service allowance message for the firstservice request from the PCEF device toward a service server handlingthe service identified by the service destination identifier.
 2. Amethod of authorizing a service with a policy and charging control (PCC)architecture, the method comprising: upon establishment or modificationof an internet protocol (IP) connectivity access network (IP-CAN)session with a user equipment (UE), requesting, by a policy and chargingenforcement function (PCEF) device, PCC rules from a policy and chargingcontrol rules function (PCRF) server; determining, at the PCRF server,PCC rules to be applied per service basis for the IP-CAN session;determining, at the PCRF server based on redirection policy criteria, aservice for which a redirection is required; submitting, from the PCRFserver to the PCEF device, the PCC rules per service basis andredirection information for the service for which the redirection isrequired, wherein the redirection information for the service for whichthe redirection is required includes a service redirection identifierindicating where the UE is to be redirected for the service for whichthe redirection is required and a redirection activation indicatorindicating whether the redirection is to be set or not; installing, atthe PCEF device, the received PCC rules per service basis and theredirection information for the service for which the redirection isrequired; upon a first service request from the UE for a serviceidentified by a service destination identifier, determining, by the PCEFdevice based on the redirection information received from the PCRF andthe PCC rules per service basis, that the service identified by theservice destination identifier is the service for which redirection isrequired, and returning toward the UE a redirection message with theservice redirection identifier and the service destination identifier;and after completion of service redirection the first service requestfor the service identified by the service destination identifierreaching again the PCEF device; verifying at the PCEF device that theservice identified by the service destination identifier can beauthorized; and submitting a service allowance message for the firstservice request from the PCEF device toward a service server handlingthe service identified by the service destination identifier.
 3. Themethod of claim 2, wherein the service destination identifier is adestination uniform resource identifier (URI) addressing the serviceserver, and the service redirection identifier is a redirection URIaddressing a site where the UE is to be redirected.
 4. The method ofclaim 2, wherein the redirection information for the service for whichthe redirection is required further includes a redirection expiryselected from a time value during which redirection takes place, anevent for which the redirection is set or reset, and a one-timeindicator indicating the redirection for the first service request inthe IP-CAN session and no further redirection for subsequent servicerequests in the IP-CAN session.
 5. The method of claim 2, wherein theredirection information for the service for which the redirection isrequired further includes at least one of a redirection code indicatinga reason for redirection, and a redirection confirmation indicatingwhether the PCRF server requires confirmation when redirection has beenapplied.
 6. The method of claim 4, wherein the redirection informationfor the service for which the redirection is required includes theone-time indicator and the method further includes disarming theredirection after having redirected the first service request from theUE for the service identified by the service destination identifier. 7.The method of claim 6, wherein upon a second service request from the UEfor the service identified by the service destination identifier, themethod further includes authorizing the service identified by theservice destination identifier at the PCEF device without redirection,and submitting a service allowance for the second service request fromthe PCEF device toward the service server handling the serviceidentified by the service destination identifier.
 8. The method of claim1, wherein the redirection policy criteria include at least one ofdynamic conditions and usage conditions.
 9. A policy and chargingenforcement function (PCEF) device of a policy and charging control(PCC) architecture for enforcing PCC rules applicable during an internetprotocol (IP) connectivity access network (IP-CAN) session establishedwith a user equipment (UE), the PCEF device comprising: a PCEFprocessing unit to determine establishment or modification of an IP-CANsession with a UE; a first PCEF interfacing unit to request, uponestablishment or modification of the IP-CAN session, PCC rules from apolicy and charging control rules function (PCRF) server in charge ofgenerating the PCC rules; and to receive, in response to the request forPCC rules, the PCC rules per service basis and redirection informationfor a service for which a redirection is required from the PCRF server,wherein the redirection information for the service for which theredirection is required includes a service redirection identifierindicating where the UE is to be redirected for the service for whichthe redirection is required; wherein the PCEF processing unit installsreceived PCC rules per service basis and the redirection information forthe service for which the redirection is required; a second PCEFinterfacing unit to receive a service request from the UE for a serviceidentified by a service destination identifier; wherein the PCEFprocessing unit determines, based on the redirection informationreceived from the PCRF and the PCC rules per service basis, that theservice identified by the service destination identifier is the servicefor which redirection is required, and determines the serviceredirection identifier; wherein the second PCEF interfacing unit returnstoward the UE a redirection message with the service redirectionidentifier and with the service destination identifier; and whereinafter completion of the service redirection the second PCEF interfacingunit receives again the service request for the service identified bythe service destination identifier; the PCEF processing unit verifiesthat the service identified by the service destination identifier can beauthorized; and a third PCEF interfacing unit to submit a serviceallowance message for the service request toward a service serverhandling the service identified by the service destination identifier.10. The PCEF device of claim 9, further comprising a memory to store theredirection information for the service for which the redirection isrequired, wherein the redirection information for the service for whichthe redirection is required includes a redirection activation indicatorindicating whether the redirection is to be set or not.
 11. The PCEFdevice of claim 10, wherein the memory stores the service destinationidentifier as a destination uniform resource identifier (URI) addressingthe service server and stores the service redirection identifier as aredirection URI addressing a site where the UE is to be redirected. 12.The PCEF device of claim 10, wherein the memory stores the redirectioninformation for the service for which the redirection is required, theredirection information for the service for which the redirection isrequired including a redirection expiry selected from a time valueduring which redirection takes place, an event for which the redirectionis set or reset, and a one-time indicator indicating the redirection forthe first service request in the IP-CAN session and no furtherredirection for subsequent service requests in the IP-CAN session. 13.The PCEF device of claim 12, wherein the redirection information for theservice for which the redirection is required includes the one-timeindicator and the PCEF processing unit disarms the redirection afterhaving redirected the service request from the UE for the serviceidentified by the service destination identifier.
 14. The PCEF device ofclaim 13, wherein upon a subsequent service request for the serviceidentified by the service destination identifier received at the secondPCEF interfacing unit from the UE, the PCEF processing unit authorizesthe service identified by the service destination identifier withoutredirection and the third PCEF interfacing unit submits a serviceallowance message for the subsequent service request toward the serviceserver handling the service identified by the service destinationidentifier.
 15. A policy and charging control rules function (PCRF)server of a policy and charging control (PCC) architecture forgenerating PCC rules to be enforced by a policy and charging enforcementfunction (PCEF) device during an internet protocol (IP) connectivityaccess network (IP-CAN) session established with a user equipment (UE),the PCRF server comprising: a PCRF interfacing unit to receive a requestfor PCC rules, upon establishment or modification of the IP-CAN session,from a policy and charging enforcement function (PCEF) device in chargeof enforcing the PCC rules; and a PCRF processing unit to determine,responsive to receiving the request for PCC rules at the PCRF server:PCC rules to be applied per service basis for the IP-CAN session; and aservice for which a redirection is required prior to the PCEF deviceverifying that the service is authorized, wherein the determination isbased on redirection policy criteria; wherein the PCRF interfacing unit,responsive to receiving the request for PCC rules at the PCRF server,submits to the PCEF device the PCC rules per service basis andredirection information for the service for which the redirection isrequired, and wherein the redirection information for the service forwhich the redirection is required includes a service redirectionidentifier indicating where the UE is to be redirected for the servicefor which the redirection is required.
 16. The PCRF server of claim 15,wherein the redirection information for the service for which theredirection is required includes a redirection activation indicatorindicating whether the redirection is to be set or not for the service,and the PCRF server further comprises a memory to store the redirectioninformation for the service for which the redirection is required. 17.The PCRF server of claim 16, wherein the memory stores the serviceredirection identifier as a redirection uniform resource identifier(URI) addressing a site where the UE is to be redirected.
 18. The PCRFserver of claim 16, wherein the memory stores the redirectioninformation for the service for which the redirection is required, andthe redirection information for the service for which the redirection isrequired includes a redirection expiry selected from a time value duringwhich redirection takes place, an event for which the redirection is setor reset, and a one-time indicator indicating the redirection for afirst service request in the IP-CAN session and no further redirectionfor subsequent service requests in the IP-CAN session.
 19. The PCRFserver of claim 15, wherein the redirection policy criteria include atleast one of dynamic conditions and usage conditions, and the PCRFserver further comprises a memory to store the redirection policycriteria.
 20. The method of claim 1, wherein the service for whichredirection is required is a service for which redirection is requiredprior to the PCEF verifying that the service is authorized.
 21. Themethod of claim 2, wherein the service for which redirection is requiredis a service for which redirection is required prior to the PCEFverifying that the service is authorized.
 22. The PCEF device of claim9, wherein the service for which redirection is required is a servicefor which redirection is required prior to the PCEF verifying that theservice is authorized.